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dnsmasq issue

Chrysalis

Senior Member
Scenario is this previously all was working until a domain I owne accidently expired.
Renewed Domain
Eventually google dns can resolve all my hostnames and the router is configured to use 8.8.8.8 as its primary dns server.

If I run nslookup on any of my hostnames on the router itself, it displays the correct result and confirms it used 8.8.8.8

If I run nslookup on my pc which is configured to use my router as its dns server it returns a "*** UnKnown can't find mail.mydomain.com: Server failed"

However if Irun nslookup on my pc for other domains they resolve.

If I run nslookup on my pc and force it to resolve my hostname via 8.8.8.8 it works.

So the router itself can resolve the hostname, my pc can resolve the hostname via google dns. My pc cannot resolve the hostname via my router. My pc can resolve other hostnames via my router.

I have flushed the dns cache on the pc multiple times as well as restarting dnsmasq on the router.

Any ideas aside from extreme's such as rebooting the router?

Does the router have some kind of negative cache it uses outside of dnsmasq?
 
Last edited:
Looks like either windows has some kind of hidden cache or the router does, as it started working last night when I didnt change anything.

I should have tested from other clients, but sadly I didnt.
 
Looks like either windows has some kind of hidden cache or the router does, as it started working last night when I didnt change anything.

I should have tested from other clients, but sadly I didnt.

There's a ridiculous (IMHO) number of caching levels involved with DNS.

1) Some clients such as Google Chrome have their own DNS cache (restart the browser)
2) Window's resolver has a DNS cache (ipconfig /flushdns)
3) Your router's dnsmasq has a DNS cache (service restart_dnsmasq)

That's on top of the ISP sometimes using cacheing servers in front of a real resolver.

So yeah, it makes troubleshooting name resolving issues kinda interesting at times.
 
Thanks for replying.

it wasnt browser as I was testing in command prompt with nslookup.

I ran ifconfig /flushdns many times.
I did restart dnsmasq with that command

so given it just magically fixed itself after a while it does seem "something" somewhere had still cached it. I also have disabled negative caching in dnsmasq.
 
ok another expired domain, and same problem again but with different error.

Code:
Server:  router.asus.com
Address:  192.168.1.253

*** No internal type for both IPv4 and IPv6 Addresses (A+AAAA) records available
 for www.xxxxxxxxx.eu.

and with google dns

Code:
Server:  google-public-dns-a.google.com
Address:  8.8.8.8

Non-authoritative answer:
Name:    www.xxxxxxxxxxx.eu
Address:  78.x.x.x

I disabled negative caching in my dnsmasq config, but even when dnsmasq is restarted the same duff result comes back, I expect it will just start working by itself at some point later on when whatever is caching it expires.

This time I did test on a different device on my lan, (my laptop) and it gets the same error. The laptop was booted up specifically to test this so no chance of it been a OS cache.
 

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